Attempting to use less-than-honest techniques to gain an unfair advantage in a game has been around for millennia, and the sport of baseball in particular possesses quite a storied history regarding cheating. In the past, players have altered balls with petroleum jelly or sandpaper, hit with lighter bats (called "corked" bats), and have even manipulated the baseball field itself. In more recent times, teams have resorted to stealing the signs of other teams via the use of wearable electronics. So in a similar manner, SparkFun's Creative Technologist, Rob Reynolds, wanted to create his own sign stealing device that could be stealthily hidden away and communicate from a long distance.
One of the main goals with this project was to make the system operate in a way such that catching the cheaters in the act would be nearly impossible. Methods such as hand signals, creating patterns of noise, and looking at a smart watch all create too much scrutiny, which is why Reynolds came up with an easily concealable pack that contains a haptic motor that can buzz in a specific pattern to indicate the signal. On the other end is a watcher who waits for the opposing team and relays that information wirelessly.
The watcher's handheld device is essentially a basic transmitter that contains a bank of four individual buttons, a battery, and a SparkFun LoRa Thing Plus - expLoRaBLE board that contains the NM180100 system in package (SiP). This setup means a single button press can wirelessly transmit the selected option up to 125 meters away. For now, there are only four signals that can be sent at any one time, but in the future, more signals can be programmed by using a combination of button presses.
As previously mentioned, the player who relies on getting the opposing team's signal is the one who wears the receiving device that buzzes a haptic motor in a certain pattern. Additionally, this setup contains a second SparkFun LoRa Thing Plus - expLoRaBLE board, along with a battery pack and external antenna for extra range. Put together, this system lets players evade detection from the traditional restrictions on technology for the use of cheating, although it should be mentioned that Reynolds does not endorse this system for use in the real world. You can watch his project showcase video here on YouTube or see his article here on SparkFun's blog.